1. Field of the Invention
The present invention relates to a mechanical arrangement for feeding fluid at a minute flow rate, which is adaptable to a multiplicity of applications.
2. Description of the Prior Art
In, for example, weaving machines, the shedding operations of the shedding motion means such as cam machines, Dobby machines or the like are transmitted to harness frames through suitable transmission means to generate the vertical movements of these harness frames, whereby the warps are allowed to make the shedding motion means. This achieves the coweaving of the warps with the wefts. The transmission means, which is applied to the shedding operation of the shedding motion means is divided into the negative type in which a spring means is used to carry out one of the upward vertical movement and the downward vertical movement of the harness frame, and the positive type in which the harness frame is driven for both of the upward and downward vertical movements thereof. (See Official Gazette No. 4-228654 to Open Inspection of Patent Applications.)
In the negative type transmission means, wire is generally used as a transmission member for the shedding operation of the shedding motion means. In order to maintain the tension of this wire, pulleys are employed. The pulleys are arranged to turn reciprocatively within the limits of a predetermined angle.
On the other hand, the positive type transmission means generally employs linking mechanisms as transmission means for the shedding operation of the shedding motion means. Swinging levers incorporated in the linng mechanisms are designed to swing reciprocatively within the range of a predetermined angle.
The pulleys and the swinging levers are both provided with bearing members and shafts which support the bearing members. The bearing members or surfaces of the shafts in contact with the bearing members are arranged to be constantly lubricated.
In a generally known construction in which the bearing members and the like are lubricated, the mating shafts are axially provided with oil holes. Similarly, the shafts have oil outflow grooves diametrically located in positions corresponding to the bearing members engaged with them, thereby allowing the oil holes and the oil outflow grooves to be communicatively connected to each other.
On the other hand, it is also known that the bearing members incorporated in the pulleys and the swinging levers are separately provided with oil holes. (See the Official Gazette mentioned in the foregoing.)
In the lubricating construction described in the foregoing, in which the shafts are axially provided with oil holes, it is difficult from the viewpoint of machining techniques to make small diameter oil holes. This difficulty is increased as the axial length of the shafts is increased.
Therefore, the oil holes in the axial directions must inevitably be increased in diameter. However, an increase in the diameter of the axial oil holes makes it difficult to allow lubricant to flow to the oil outflow grooves having smaller diameters, thereby causing frequent oil shortages in the shafts. This results in the problems of heating and singeing. Therefore, in order to prevent such problems, lubncant is required to be fed under a high pressure from the oil holes to the oil outflow grooves, thereby bringing about an oil feeding system having a much larger capacity.
On the other hand, when the bearing members are separately arranged to be provided with oil holes, these oil holes are required to be periodically replenished with lubricant. Replenishment of lubricant necessitates the operational stoppage of, for example, weaving machines each time it is performed. This causes a drop in the operating efficiency of the machines as well as an increase in the working trouble of a machine operator.